Recovery plates and method of making same



Aug. e, 1957 A. F. BUTTNER ETAL M 2,801,917'

RECOVERY PLATES AND METHOD 0E MAKING SAME Filed .July `15, 1955 IN VEN TORS ARNOLD F. BUTTNER CALVIN E. CAMP United States Arnold F. Buttner and Calvin E. Camp,

South Gate, Calif. t

`Application July 15, 1955, Serial No. 522,229 Claims. (Cl. 75-138) The present invention relates generally to recovery of metals and more particularly to a recovery plate for recovering metals from solutions of their ores, and more particularly recovery of copper from a leach solution of copper ore.

The primary object of this invention is to provide a recovery plate composed of aluminum and other materials which, when suspended in an` acid solution of the metallic ore, causes the copper to deposit on the plate in the form of loosely adherent occulent particles.

Another object of this invention is to provide a recovery plate which` is adapted for suspension in the leach solution, and for periodic withdrawal for removal of the flocculent` metal which 4collects on the plate during immersion thereof in the leach solution.

Another object of this invention is to provide a recovery plate which is self generating or capable of producing local galvanic action and functions somewhat after the manner of conventional electrolysis ore recovery but without the use of` external source of electrical power.

Another object of this invention is to provide a recovery plate which is long lasting and is not subject to pitting.` i

Another object of this invention is to provide a recovery plate containing elements which apparently inhibit even the transient formation of unwanted products such as aluminum hydroxide, thus reducing contamination of the recovered metal and prolonging the useful life of the plate.

Finally, it is an object to provide a recovery plate of the aforementioned character which is simple, safe and convenient to use and which` will give generally ecient and durable service.

With these and other objects definitely in view, this invention consists` in the novel construction, combination and arrangement of elements and portions, as will be hereinafter fully describedV in the specification and particularly pointed out in the claims, and illustrated in the drawing which forms a material part of this disclosure, and in which:

Fig. 1 is a perspective View of a plate; and

Fig. 2 is a diagrammatic sectional view showing the manner in which the plates are used.

The plate is composed basically of aluminum with small quantities of other metals and elements added, the plate being cast or poured into any desired shape and size. The porosity of the plate is easily controlled to suit the processing of various ores. The plate causes the precipitation of metals below hydrogen in the electrochemical series and also some metals above hydrogen but below aluminum in the series.`

A typical plate may be composed as follows:

Element:

Zinc .3Q Nickel .02 Chromium .07 Titanium .06 Lead .01 Tin .0l Aluminum Balance This plate extracts extremely fine grain metal in the form ofa flocculent precipitate on the surface of the plate. To secure a coarser grained metal deposit the quantities of silicon, nickel and titanium may be increased and a small quantity of antimony introduced,ras follows:

The above examples are obtained from spectrogtaphic analysis of plates found to be satisfactory in the recovery of copper and the proportions of the various elements should `not be construed as` limiting. The exact proportions may be varied accordingto the ore being processed. and the metal beingV recovered.

The plate is preferably made by first fusing aluminum ingots, together with the additional elements, at a temperature of approximately- 155300^ The elements are preferably in nely powdered form although this is not essential. If it isjdesired` to fuse the titanium completely, the initial fusing temperature may be raised to 4suit or the titanium may be added in finely powdered'form. The mixture is agitated andV a. quantity of commercial aluminum fluxing salt is,` added; For a poundaluminum ingot the quantity of flux should be about 8 pounds., After` the addition ofthe flux and thorough agitationfthe mix is cooled to l020 F. and a further 10.` pounds of aluminum flux is added withfurthrer agitation. The mix is then heated to a temperature between 1220 and 1340 F. and a further 2 pounds of aluminum flux s added. The mix is` again` agitated and` the temperature is held constant for approximately seven minutes, after which the mix maybe-poured into` a suitable vformI tomake the plate. The plate may be allowed to cool naturally or may be quenched in water when the temperature has dropped to 600 F. according to the texture demanded. The mold may have means for forming apertures near one end of the plates, or the molded plates may be drilled or otherwise adapted for suspension.

In use, the plate is suspended in a leach solution of an acid, usually sulphuric and the ore to be processed. The plate releases nascent hydrogen from the acid of the solution and causes precipitation of the metal suspended in solution, the metal being deposited on the surfaces of the plate itself. The additional elements in the plate have the property of inhibiting even the transient formation of aluminum hydroxide and the aluminum does not appear to enter directly into the chemical reaction to the extent experienced in the older, well known recovery processes, so that the rate of decomposition of the plate is phenomenally greatly reduced and contamination of the deposited metal is virtually eliminated.

The plate is self generating and requires no outside Patented Aug. 6, 17957 Percent byV Weightr source of electrical power for its operation. In the plate, small particles of aluminum are separated from Small particles of the other metals by silicon in the presence of the acid in solution which acts as an electrolyte. The resultantminute electricalcurrents set upA have an effect similar to that of electrolysis and assist in deposition of the metal onto the plate. Porosity of the plate may be controlled by varying the type and quantity of flux added and by varying the temperatures during mixing.

The plate is best formed by casting the prepared mix in a suitable moldto produce a flat plate as in Fig. 1 o'f the drawing, said plate having apertures 12 adjacent one end to provide means for suspending the plate. In use, several plates 10 may be suspended from suitable support rods 14 which are passed through the apertures 12, the plates being immersed in a leach solution 16 contained in a tank 18. The solution 16 contains approximately3`% acid in water and is used to leach the metal to be recovered from its ore 20, which remains at the bottom of the tank. When the plates 10 are immersed, the` metal in the solution is deposited on the plates in the form ofthin layers 22, and these layers of metal deposit are easily removed from the plates at intervals when a suicient thickness of metal has been built up.

' The operation of this invention will be clearly comprehende'dfrom a consideration of the foregoing description of the mechanicaldetails thereof, taken in connection withthe drawing and the above recited objects. It will be obvious that all said objects are amply achieved by this invention. i

Further description would appear to be unnecessary. It is understood that minor variation from the form of the invention disclosed herein may be made without departure from the spirit and scope of the invention, and that the specification and drawing are to be considered as merely illustrative rather than limiting.

VWe claim:

1. A recovery plate for recovery of a metal from an acid solution of its ore by deposition of the metal onto the"plate,rco mprisng: the product formed by fusing aluminum with a mixture of at least two other elements below aluminum in the electrochemical series while adding'an aluminum uxing salt; cooling the resulting product to approximately 1020 F. while maintaining the same in a substantially molten state and adding more aluminum fluxing salt; reheating the resulting product to approximately 1280 F. and adding more aluminum fluxing salt and maintaining a constant temperature for 5 to 10 minutes; pouring the resulting product into a mold to achieve plate form and allowing to cool. 2. A method for making a recovery plate for recovery of a metal from an acid solution of its ore, comprising: fusing aluminum with a mixture of at least two other elements below aluminum in the electrochemical series while adding an aluminum fluxing salt; cooling the resulting product to approximately 1020 F. while maintaining the same in a substantially molten state and adding more aluminum iluxing salt; reheating the resulting product to approximately l280 F. and adding more aluminum tluxing salt and maintaining a constant temperature for 5 to 10 minutes; pouring the resulting product into a mold to achieve plate form and allowing to cool; and providing the molded plates with means for suspension thereof.

3. A method for making a recovery plate for recovery of a metal from an acid solution of its ore, comprising: fusing aluminum with a mixture of other elements below aluminum in the electrochemical series at a temperature on the order of 1530 F. and adding an aluminum fluxing salt while agitating the mixture; cooling the mixture to approximately 1020 F. and adding more aluminum fluxing salt; reheating the mixture to a temperature between l220 and l340 F. and adding more aluminum fluxing salt; maintaining the last mentioned temperature for a period on the order of 7 minutes; and pouring the mixture into a mold.

4. A method for making a recovery plate for recovery of a metal from an acid solution of its ore, comprising: fusing aluminum with a mixture of other elements below aluminum in the electrochemical series at a temperature on the order of 1530'J F. and adding an aluminum tluxing salt while agitating the mixture; cooling the mixture to approximately 1020 F. and adding more aluminum fluxing salt; reheating the mixture to a temperature between 1220" and 1340 F. and adding more aluminum fluxing salt; maintaining the last mentioned temperature for a period on the order of 7 minutes; pouring the mixture; and quenching the plate when the temperature reaches 600 F.

5. A method for making a recovery plate for recovery of a metal from an acid solution of its ore, comprising: fusing aluminum with a mixture of silicon and at least two elements from the. group containing copper, iron, manganese, zinc,vnickel, chromium, titanium, lead, tin and antimony, while adding an aluminum fluxing salt; cooling the mixture while maintaining the mixture in a substantially molten state and adding more aluminum fluxing salt; reheating the mixture and adding more aluminum fluxing salt and maintaining a constant temperature for 5 to 10 minutes; pouring the mixture into a mold to achieve plate form and allowing to cool; and providing the molded plates with means for suspension thereof. A Y

References Cited in the file of this patent The Iron Age, August 13, 1942, page 70. 

1. A RECOVERY PLATE FOR RECOVERY OF A METAL FROM AN ACID SOLUTION OF ITS ORE BY DEPOSITION OF THE METAL ONTO THE PLATE, COMPRISING: THE PRODUCT FORMED BY FUSING ALUMINUM WITH A MIXTURE OF AT LEAST TWO OTHER ELEMEMTS BELOW ALUMINUM IN THE ELECTROCHEMICAL SERIES WHILE ADING AS ALUMINUM FLUXING SALT; COOLING THE RESULTING PRODUCT TO APPROXIMATELY 1020*F. WHILE MAINTAINING THE SAME IN A SUBSTANTIALLY MOLTEN STATE AND ADDING MORE ALUMINUM FLUXING SALT; REHEATING THE RESULTING PRODUCT TO APPROXIMETELY 1280*F. AND ADDING MORE ALUMINUM FLUXING SALT AND MAINTAINING A CONTENT TEMPERATURE FOR 5 TO 10 MINUTES; POURING THE RESULTING PRODUCT INTO A MOLD TO ACHIEVE PLATE FORM AND ALLOWING TO COOL. 